Duplex valve



Jl lne 30, 1953 P. c. SYMMONS DUPLEX VALVE Filed June 5, 1951 NVENTOR.

Patented June 30, 1953 UNITED STATES OFFICE This invention relates to avalve structure of the type which has two separate inlet openings, twoseparate discharge openings, one for each inlet opening, a valvecontrolling communication. between each inlet opening and its dischargeopening, and means common to both valves for operating themsimultaneously.

One object of the invention is to provide a valve of this type which isso constructed that when the valve operating member is actuated to closethe valves, said member will automatically center itself so as to effecta tight closure of both valves even though one of the valves has @becomemore or less worn.

Other objects of the invention are to improve valves of this type invarious particulars which will be pointed out in the followingdescription.

In the drawings wherein I have illustrated a selected embodiment of theinvention:

Fig. l is a sectional view of a valve embodying the invention takensubstantially on the line II, Fig. 4, and showing both valves closed.

Fig. 2 is a view similar to Fig. l but showing the manner in which thevalve-operating member adjusts itself to effect a tight closure of bothvalves.

Fig. 3 is an enlarged section on the line 33, Fig. 1.

Fig. 4 is a section on the line 4-4, Fig 1.

The valve structure herein shown comprises a valve casing I which isprovided with two separate inlet openings 2 and 3, and also with twodischarge openings 4 and 5. The inlet opening 2 communicates through aport 6 with a valve chamber I with which the discharge opening 4communicates, and the inlet opening 3 communicates through a port 8 witha separate valve chamber 9 with which the discharge port 5 communicates.

The port 6 is controlled by valve II! that is provided with the usualvalve washer I! which seats against the valve seat I2. The port 8 iscontrolled by a similar valve I3 having a valve washer I4 which isadapted to seat against the valve seat I5.

The valve casing is provided with a central chamber 58 which isseparated from the valve chamber 1 by a partition I! and which is alsoseparated from the valve chamber 9 by another partition I8. The bodyportion of the valve II] extends through the partition I! into thechamber I5, and the body portion of the valve I3 extends through thepartition I8 into chamber IS.

The valves I and I3 are axially alined and are oppositely disposed, thevalve I0 being closed 3 Claims. (Cl. 137--630.18)

against its valve seat I2 by a movement to the left, as in Fig. l, andthe valve 13 being closed against its valve seat It by a movement to theright.

Both valves Is and I3 are controlled by a valve-operating memberindicated generally at I9 and which is situated within the chamber I6,said valve member having an operating handle 20 which extends through aslot H with which the valve casing I is provided.

Said valve-operating member I9 is provided with means which cooperateswith both valves in such a way that when the member I?! is turned in onedirection both valves will be opened simultaneously, and when turned inthe opposite direction both valves will be closed.

As herein shown, the valve-operating member has two oppositely disposedaxially alined exteriorly screw threaded portions 22 and '23 whichcooperate with the valves I0 and I3 to open and close them as thevalve-operating member is turned. The screw threads on the portion 22are right hand screw threads and engage mating interior screw threadsformed in the walls of a recess 25 with which the valve I0 is provided.The screw threaded portion 23 has left hand screw threads which engagemating interior screw threads formed in the walls of a recess 26 withwhich the valve I3 is provided.

The valves I0 and I3 are free to move toward and from their seats butare held from rotative movement so that the turning of thevalve-operating member I9 will operate to open or close the valvessimultaneously dependin on the direction in which the said member isturned.

The means for holding the valves from rotative movement consists of acollar 27 which is welded to or otherwise rigidly secured to the valveand which is provided in its periphery with a notch 28 that receives arib 29 formed on the valve casing and located within the chamber I6.

In order to provide a tight closing of both valves even though one valveor its valve seat may become worn more or less, the slot 2I in the valvecasing and through which the handle 20 extends is made somewhat widerthan the thickness of the handle, as shown in Figs. 1 and 2.

If during the closing movement of the valves resulting from swinging thehandle downwardly from the full to the dotted lines position, Fig. 4,the valve I3 engages its seat while the valve I0 is still separated fromits seat, continued turning movement of the handle will cause the valveoperatin member I9 to move bodily toward the left because of the screwthreaded engagement between the portion 23 and the valve l3 which isheld from movement by its engagement with its valve seat. This bodilymovement to the left of the valve operating member together with themovement which is given to the valve ill by the continued turningmovement of the valve operating member will bring said valve l6 tightlyagainst its seat, and thus both valves will be seated with the samevalve seating pressure.

30 indicates suitable packing in each of the partitions I1 and I8 toprevent leakage from either inlet port into the central chamber I6.

The valve casing can conveniently be made in two sections 3! and 32which are secured together by screws 33 I claim:

1. A valve structure comprising a valve casing provided with twoseparate inlet openings and a separate discharge opening communicatingwith each inlet opening through a separate port, two separate axiallyalined oppositely disposed valves, one controlling the port connectingone inlet opening and its discharge opening and the other controllingthe other port connecting the other inlet opening and its dischargeopening, both valves being movable in the direction of their common axisto open and close the ports, a valve operating member situated betweensaid valves and mounted for turning movement about the common axis ofthe valves, said valve operating member having means cooperating withboth valves by which turning movement of said memher in one directionwill move the valves away from each other in the direction of theircommon axis to close both valves and turning movement in the oppositedirection will move the valves in an opposite axial direction to openboth valves, said valve operating member being free to movelongitudinally of the common valve axis, whereby when the valves areclosed both valves will be subjected to the same valve-closing pressure.

2. A valve structure comprising a valve casing provided with twoseparate inlet openings and a separate discharge opening communicatingwith each inlet opening, two separate axially alined oppositely disposedvalves, one controlling the communications between one inlet opening andits discharge opening and the other controlling the communicationbetween the other inlet opening and its discharge opening, a valveoperating member situated between said valves and mounted for turningmovement about the common axis of the valves, said valve operatingmember having a, right hand screw threaded connection with one valve anda left hand screw threaded connection with the other, whereby turningmovement of the valve operating member in one direction opens bothvalves and turning movement in the other direction closes both valves,said valve operating member being free to move longitudinally of thecommon valve axis, whereby during the closing movement of the valvesboth valves will be subjected to the same valve-closing pressure.

3. A valve structure as defined in claim 2 in which means are providedto restrain said valves from turning movement while permitting them tomove in an axial direction into opening or closing positions.

PAUL C. SYMMONS.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,521,724 Sourh Jan. 6, 1925 1,565,794: Clifiord Dec. 15, 1925

